1. Field of the Invention
The present invention relates to an inductor and a method for manufacturing the same, and more particularly, to an inductor with improved inductance characteristics and a method for manufacturing the same.
2. Description of the Related Art
A multilayer power inductor is mainly used in a power circuit such as a DC-DC converter of a portable electronic device and particularly used in a high current due to its characteristics of suppressing magnetic saturation in terms of material and structure. Since the multilayer power inductor has a disadvantage that an inductance L value is greatly changed according to application of a current compared to a wire-wound power inductor but is advantageous to miniaturization and thinning, it can respond to the recent trend of electronic components.
A typical multilayer power inductor consists of a core layer having a coil type conductive pattern, a magnetic layer for covering the core layer, external electrodes for covering both ends of the magnetic layer, etc. Here, the conductive pattern forms a final inductor by configuring a laminate through printing of a conductive material and lamination of the magnetic layer on the core layer and pressing and sintering the laminate.
In the inductor having the above structure, the higher the magnetic material filling density of the magnetic layer, the higher the permeability of the magnetic layer. Thus, the inductance characteristics are improved. However, as for the device body of the same inductor, since the miniaturization of the coil type conductive pattern is very limited, a reduction in the thickness of the core layer can finally increase the magnetic material filling density of the magnetic layer. However, since a typical core layer is manufactured using a copper clad laminate etc. as a base, there are limitations in reducing the thickness of the core layer.
Further, the above manufacturing process of the inductor has problems such as the spread of the electrode in the printing process for forming the conductive pattern and the deformation of the previously formed conductive pattern due to the pressing and sintering processes. Particularly, the laminating and pressing processes cause the deformation in vertical alignment of the coil type conductive pattern and the sintering process causes the shrinkage of the coil type conductive pattern. The deformation of the coil type conductive pattern like this deteriorates the inductance characteristics of the inductor. Thus, it is difficult to implement low resistance high current characteristics required for a power inductor.